Rotary clinker cooler



May 12, 1942.

A. J. ROUBAL vROTARY CLINKER COOLER Filed Nov. 25, V1940 mmv jatentec May i2, 1942 UNITED STATES ROTARY CLINKER COGLER Alexander J. Roubal, Wauwatosa, Wis., assignor to Allis-Chalmers Manufacturing Company, Milwaukee, Wis., a corporation of'Delaware Application November 25, 1940, Serial. No. 367,021

4 Claims.

This invention relates generally to cooling apparatus and more particularly to the type of apparatus adapted for use in cooling hot granular materials,

The cooling of lime is, by way of illustration, in many instances accomplished by passing a large quantity of cooling air through a rotary conveying drum in counterflow relation with respect to the movement of the lime therethrough. In most arrangements of this type, the cooling air passes through the drum in direct contact with the heated lime therein but it is also common practice to indirectly effect the desired degree of cooling by passing the lime through mulile tubes which extend longitudinally throughout the interior of the drum. This latter arrangement avoids fogging the cooling air with dust which in turn results in other advantages as stated in the patent to R. D. Cheesman et al. No. 2,218,873, Tube cooler, dated October 22, 1940. Consequently, indirect cooling is in some instances preferred with respect to kiln and cooler arrangements in which the cooling air which is heated in passing through the drum is introduced into the associated kiln to support combustion therein.

The quantity of air which is necessary in order to cool lime or other granular material to the required degree is, as particularly pointed out in the patent to R. C. Newhouse, No. Y2,218,476, dated October 15, 1940, Rotary cooler, greatly in excess of that required for combustion purposes and its introduction into the kiln materially reduces the overall efficiency of the combination comprising the kiln and cooler.

It is therefore an object of this invention to provide an improved indirect cooler and furnace arrangement which adequately cools the hot material discharged from the furnace without intro ducing excess air into the furnace.

Another object of this inventio-n is to provide an improved indirect cooler in which precooling of hot material is eiected entirely by :combustion air and in which the nal cooling is effected entirely by air in excess of that required for combustion Within the associated furnace.

Still another object of this invention is to provide -an improved indirect cooler structure which provides separate noncommunicating precoolingl and nal cooling chambers through which the clinker passes,

The invention accordingly consists of the various features of construction, combinations of elements and arrangements of parts as more particularly pointed out in the appended claims and in the detailed description in which:

Fig. 1 is a longitudinal vertical section of a kiln and cooler arrangement embodying the invention;

Fig. 2 is a transverse vertical section of the cooler taken on line II-II of Fig. l; l

Fig. 3 is another transverse vertical section of the cooler taken on line III--III of Fig. 1; and

Fig. 4 is still another transverse vertical section of the cooler and the stack connected housing taken on line IV-IV of Fig. 1.

Referring to the drawing and particularly Fig. l, it is seen that the invention is illustrated in connection with the cooling of lime or other granular materials discharged from a kiln or furnace I having a burner 2 of conventional construction.. 'Ihe hot lime uponi leaving the kiln enters a -combined hood and spout structure 3 which conducts lime into the front or receiving end of a cooler 4 which is mounted for rotationl on axially spaced, conventional roller supporting structures 5. Rotation of the cooler maybe affected by the usuall ring gear and` motor driven pinion arrangement designated generally by numera] I0. f

The rotary cooler comprises, particular reference being also had to Figs. 2, 3 andV 4, an elongated cylindrical drum 6 having disposed therein a centralair tube 'I which coacts with the interioi` surface ofthe drum 6 and forms there- With an annular cooling medium conducting space 8 and an annular series ofspaced muflie tubes 9 which surround the central air tube l -and which are spaced from the interior surface of the drum 6 and from the exterior surface of the air tube l. In other Words, the muiiie tubes 9 are disposed within and extend through'the annular cooling medium conducting space 8. The mufiie tubes 9 are supported by and extend through -a front header plate II, a rear header plate I2, and an intermediate partition plate I3. The central air tube 'I which also extends through and is supported in part by the partition plate I3, has its forward end disposed in abutting relation With the inner surface of the front header plate Il and has its rear end disposed in abutting relation With a baille plate I4 which is spaced from the rear header plateA I2 and which has a central opening I'6 therein placing the interior of the air tube 'I in communication With the space I5 provided between the rear header pl-ate I2` and the baffle plate I4. Y

The front and rear header plates I I and I2` are disposedadjacent to and close the respective ends of the drum 6 and the partition plate I3 coacts with said header plates and divides the interior of the drum, i. e., the annular cooling medium conducting space 8, into a precooling chamber I1 and a final cooling chamber I8. The air tube 1 is provided with an annular series of openings I9 disposed immediately in front of the with an annular series of openings 2| disposedl immediately rearward of the front header plate so that the cooling medium entering the rear end of the precooling chamber I1 through the openings I9 will flow forward therethrough and out the openings 2|. A cooling medium collecting housing 22 encloses that portion of the drum 6 which contains the cooling medium discharge openings 2| and the combined hood and spout structure 3 is provided with a uid conduit portion 23 which communicates with the interior of the kiln and which is connected to the cooling medium collecting housing 22 so that when a combustible supporting cooling medium such as air is employed, the cooling air which passes out of the precooling space I1 through the openings 2| is conducted into the kiln to support `combustion therein.

The front end of the drum 6 is provided with a refractory lining 24 which is in part spaced from the front header plate |I so as to form therebetween a material receiving chamber 26 and which is arranged to provide a central opening 21 through which extends the material conducting spout portion of the combined hood and spout structure 3. The rear end'of the drum 6 is provided with a hood structure 28 adapted toreceive the cooled material leaving the muiile tubes 9 and this hood structure is provided with a central opening 29 through which extends an air admission conduit 3I. A blower 32 has its discharge 33 connected with the conduit 3| to deliver cooling air into the space I between the bafiie plate I4 and the rear header plate I2. A relatively short conduit 34 of less diameter than the conduit 3| extends in sealed relation through the central opening I6 in the baffle plate I4 and coaxially into the discharge end of the conduit 3|. Consequently, a portion of the air passing through the conduit 3| enters the conduit 34 and passes therethrough and into the central air tube A 1. A damper 36 disposed Within the conduit 34 controls the quantity of cooling air entering the central air tube 1. -As previously indicated, the air which enters the rear end of the central air tube 1 iiows forward therein, out through the openings I9, forward through the precooling zone I1, then out through the openings 2| into the housing 22 and then through the conduit 23 into the kiln l.

The drum 6 is also provided with another annular series of cooling medium discharge openings 31 disposed immediately rearward of the partition plate I3 and with a second cooling medium collecting housing 38, which may be connected with a stack structure 39 (see Fig. 3) and which is disposed in sealed relation about that portion of the drum which contains the openings 31. The air which enters the space I5 from the conduit'3I then flows forward through the final cooling space I8, out through the openings 31 and into the housing 38 and then into the stack 39.

The interior of the precooling and final cooling spaces are preferably provided with a series of axially spaced and staggered annular baffle plates 4| and 42 which are secured to the outer surface of the central air tube and to the inner surface of drum 6, respectively, as best shown in Figs. 2 and 3. The baille plates I4, 4| and 42, and the combined partition and baffle plate 20 coact with each other and with the muiiie tubes 9 to direct the cooling medium flowing through the precooling and final cooling spaces transversely with respect to the longitudinal axis of the muflle tubes 9 to thereby increase the rate of heat exchange between the material confined within said muiile tubes and the cooling medium flowing through said spaces.

The capacity of the blower and the dimensions of the air tube 1 of the precoolingvand final cooling chambers I1 and |8, respectively, of the cooling medium discharge openings I9, 2| and 31, and of the conduits 3| and 34 are preferably so correlated that the quantity and the temperature of the combustion supporting cooling medium flowing out of the precooling chamber l1 and into the furnace through the openings 2|, housing 22 -and conduit 23, is commensurate with the combustion requirements of said furnace and that the quantity of cooling medium flowing through the final cooling space and to the stack 39 through the openings 31 and the housing 38 is sufficient to further cool the precooled material to the required predetermined degree. The proper dimensions for a particular application can be readily and accurately determined by any one skilled in the art and therefore sample calculations and a further description in this connection are not necessary for a complete understanding of this invention. However, a regulating damper such as the damper 36 should preferably be employed in order to compensate for variations in draft conditions and other variable factors which cannot be accurately predetermined for all conditions of operation.

The construction and the operation of the cooler 4 should be obvious in view of the foregoing detailed description. However, a feature of particular importance is the provision of separate non-communicating precooling and final cooling chambers, as this construction enables the use of a combustion supporting precooling medium in quantities commensurate with the combustion requirements of the kiln or furnace with which the precooling chamber communicates. In addition, the use of a precooling chamber which is entirely free from communication with the interior of the hot material conductor extending therethrough prevents any reaction taking place between the hot material which is to be cooled and the particular combustion supporting precooling medium employed and pre- `.vents the combustion supporting medium from ulation of the burner and/or furnace is greatly simplified.

'Ihe invention is of'general application and although it has been disclosed in connection with a munie tube cooler in which both the precooling and final cooling chambers are free from communication with the interior of the hot material conductor, it should be understood that the nal cooling chamber may communicate with theV interior of the hot material conductor, that different cooling mediums may be employed in the precooling and nal cooling chambers and that it is not intended to limit the invention to the exact details of construction and mode of operation herein shown and described as various modifications within the scope of the appended claims may occur to persons skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. In combination With a furnace, means for conveying and cooling the hot material discharged from said furnace comprising an elongated drum, means dividing the interior of said drum into separate, non-communicating precooling and final cooling chambers, a plurality of material conveying conduits extending through said dividing means and through said precooling and said final cooling chambers, an air tube extending through said final cooling chamber, through said dividing means, and into said precooling chamber, fluid conveying means operatively connecting said precooling chamber with the combustion space of said furnace, and means including said air tube operative to flow a quantity of combustion supporting cooling medium commensurate with the combustion requirements of said furnace through said precooling chamber and to flow a quantity of cooling air sufficient to further cool said material to a predetermined degree through said final cooling chamber.

2. In combination with a furnace, means for conveying and cooling the hot material discharged from said furnace comprising an elongated rotary drum, means dividing the interior of said drum into separate, non-communicating precooling and final cooling chambers, a central air tube extending through said final cooling chamber, through said dividing means, and into ing said precooling chamber with the combustion space of said furnace, and means including said air tube operative to floW a quantity of combustion supporting cooling medium commensurate with the combustion requirementsV of said furnace through said precooling chamber and said fluid conveying means and to flow a quantity of cooling air sufcient to further cool said material to a required predetermined degree through said final cooling chamber.

3. A cooler for granular materials comprising an elongated drum, means dividing the interior of vthe drum into separate,` non-communicating precooling and final cooling chambers, a central air tube extending through said nal cooling chamber, through said dividing means, and into said precooling chamber, a plurality Vof spaced mulile tubes arranged to surround said air tube and to extend through said dividing means and through said precooling and final cooling chambers, and means including said air tube for effecting a flow of separate streams of cooling air through said precooling and said final cooling chambers.

4. In combination with a furnace, a hot material conveying conductor arranged toreceive the hot material discharged from said furnace, a precooling conductor, a final cooling conductor, said precooling and nal cooling conductors being arranged to flow separate streams of cooling medium in non-mixing relation with respect to each other and in heat exchanging relation with respect to different portions of said material conductor and out of contact with the hot material passing therethrough, and means for effecting the W of said separate streams of cooling medium including connections operative to conduct the stream of cooling medium which flows through said precooling conductor and in heat exchanging relation with respect to a portion of said material conductor into the combustion space of said furnace.

ALEXANDER J. ROUBAL. 

